Temporary keratoprosthesis and method of its application

The present invention relates to the field of methods or devices used in eye surgery and can be used as a temporary keratoprosthesis to visualize the tissue structure of the posterior segment of the fundus in the absence of the cornea of ​​the eye.

Prior Art

A temporary keratoprosthesis device is known (see Benner JD, Landers MB III, An infusion temporary keratoprosthesis for pars plana vitrectomy, Am J Ophthalmol, 1996; 122 (4): 579-580), which is a transparent optical lens in the visible range, Close to the optical power of the cornea, and having the shape of a fungus, the length of the trunk of which is approximately equal to the thickness of the cornea of ​​the eye, and the radius of curvature of the surface of the cap is approximately equal to the curvature of the cornea of ​​the eye. The diameter of the cap is larger than the diameter of the stem. At the same time, for a better fixation of the keratoprosthesis on the surface of the eye, along the periphery of the cap, at the maximum distance from its center, hemming holes are made, providing the possibility of filing the keratoprosthesis to the surface of the eye.

The method of using the analogue (see Benner JD, Landers MB III, An infusion temporary keratoprosthesis for pars plana vitrectomy, Am J Ophthalmol, 1996; 122 (4): 579-580) is that the eye is carved into a cornea in the form of a circular aperture With a diameter slightly smaller than the diameter of the pedicle of the keratoprosthesis and in this hole the stem of the keratoprosthesis is firmly inserted. Further, through the hemispherical holes, the keratoprosthesis is hemmed to the surface of the eye. This ensures reliable sealing of the eye and fixation of the keratoprosthesis on its surface. After this, in order to restore the original form, a liquid, in particular perfluorodecalin, is injected into the eye under excess pressure.

The disadvantage of the analogue is that during the installation the leg of the keratoprosthesis injures the surrounding tissues of the eye. This leads to frequent swelling and postoperative complications. In addition, because of the large thickness of the keratoprosthesis, the image being imaged has a low resolution.

The closest to the claimed device in terms of technical essence is the device of a temporary keratoprosthesis without a leg (Landers wide-field trunkless TCR, Ocular Instruments), described in detail in the article "An Improved Temporary Keratoprosthesis". (Retina Today, 2014, Vol. 9, N. 6, p. 42) and is a transparent lens in the visible range with a curvature of the upper optical surface close to the curvature of the cornea and an optical force close to the optical power of the cornea of ​​the eye. To fix the keratoprosthesis on the surface of the eye along its periphery, at the maximum distance from the center, hemming holes are made, providing the possibility of filing the keratoprosthesis to the surface of the eye.

The closest to the claimed method of technical essence is the method of application of the prototype, described in the article "An Improved Temporary Keratoprosthesis". (Retina Today, 2014, Vol. 9, N. 6, p. 42) and consists in the fact that the eye is carved by the cornea in the form of a circular orifice with a diameter smaller than the diameter of the temporary keratoprosthesis. Further, through the hemispherical holes, the temporary keratoprosthesis is hemmed to the surface of the eye so that it fits as closely as possible to the tissues surrounding the hole in the cornea. After this, to restore the original form to the eye, under the excess pressure, a liquid is supplied, in particular perfluorodecalin.

The disadvantage of the prototype is the poor tightness of the connection between the temporary keratoprosthesis and the tissues of the eye.

Disadvantages are due to the fact that it is practically impossible to fasten the temporary keratoprosthesis on the eye surface with the aid of blind holes so that the eye-filling liquid does not leak through the gap between the surface of the temporary keratoprosthesis and the eye.

Object of the invention

The object of the invention is to seal the gap between the temporary keratoprosthesis and the eye surface.

The goal is achieved by the fact that in the device of the temporary keratoprosthesis in the form of a lens that is transparent in the visible range with a curvature of the upper optical surface close to the curvature of the cornea and an optical force close to the optical power of the cornea of ​​the eye, the lens is rigidly attached to the surface of the thin filigree ring with the outer Diameter larger than the diameter of the lens,

And also the method of its use, consisting in the fact that the eye is carved into a cornea in the form of a round hole with a diameter smaller than the diameter of the temporary keratoprosthesis, and a temporary keratoprosthesis for the filigree ring is hemmed to the surface of the eye so that it lies against the tissues surrounding the hole in Cornea. After that, the conjunctiva around the prosthesis is stitched with a sutured suture, the thread of which is pulled so that on the surface of the thin ring of the temporary keratoprosthesis around the lens a fold of the conjunctiva forms.

The novelty of the claimed features consists in the rigid fixing of the lens with the curvature of the upper optical surface close to the curvature of the cornea and the optical force close to the optical power of the eye cornea on the surface of a thin filigree ring with an outer diameter larger than the diameter of this lens. And also that the conjunctiva around the prosthesis is stitched with a sutured suture, the thread of which is pulled so that a fold of the conjunctiva forms around the lens on the surface of the thin hemispherical ring of the temporary keratoprosthesis.

The positive effect is achieved due to the fact that the fold of the conjunctiva formed on the surface of the thin filigree ring seals the gap between the surface of the temporary keratoprosthesis and the surface of the eye.

The essence of the invention is explained by the drawings.

Referring to Fig. 1 is a top view of a specific implementation of the proposed device.

Referring to Fig. 2 is a cross-sectional view of the device of FIG. 1.

Referring to Fig. 3 is a top view of the proposed device sewn to the eye with a sewn sutured conjunctiva.

Referring to Fig. 4 is a cross-sectional view of the device according to the invention, which is sewn to the eye with a conjunctiva sewn with a suture.

Referring to Fig. 5 is a top view of the proposed device attached to the eye after the sachet is tightened.

Referring to Fig. 6 is a cross-sectional view of a device sewn to the eye with a tightened sachet seam.

DETAILED DESCRIPTION OF THE INVENTION

An example of a specific implementation of the proposed device is shown in FIG. 1 and represents a 1 - transparent in the visible range of the lens with the curvature of the upper optical surface closest to the corneal curvature and optical power, near optical power of the cornea, which is rigidly fixed to the surface 2 - the thin podshivnoy rings with an external diameter larger than the diameter of the lens (1). In the ring 2 there are filigree holes - 3.

Referring to Fig. 2 is a cross-sectional view of the same (Figure 1) device illustrating its construction.

The installation of the device according to the invention is shown in Fig. 3 above and in FIG. 4 in cross-section, wherein 4 - Eye, 5 - suture providing temporary fixation keratoprosthesis over the eye, 6 - podshivnoy purse string suture around the ring 2, 7 - the conjunctiva of the eye.

Before the temporary keratoprosthesis is installed, a part of the cornea of ​​the eye (4) is removed. After that, on the eye tissue (4), around the hole in the cornea, using the suture material (5) through the filing holes (3), the temporary keratoprosthesis is sewn onto the surface of the eye (4), and the conjunctiva (7) of the eye (4) around the filigree ring (2) stitched with a cord suture (6). The final step is shown in FIG. 5 and Fig. 6. At this stage, the suture seam (6) is pulled in such a way that the fold of the conjunctiva (7) formed by the pulling is located on the surface of the hem ring (2), as shown in FIG. 5 and FIG. 6, and sealed the gap between the hem ring (2) and the eye (4).